Process for the odor removal of malodorous sulfur containing olefinic derivatives

ABSTRACT

There is provided a process for the upgrading of a malodorous, sulfur-contaminated, aliphatic, aromatic or cycloaliphatic olefinic derivative or mixture thereof which involves contacting said malodorous, sulfur-contaminated derivative or mixture thereof with from 1 to 2 equivalents of a per(lower)alkanoic acid per mole of sulfur in said olefinic derivative, the amount of said acid being sufficient to oxidize the sulfur content therein, maintaining the treated solution at a temperature ranging from about -10*C. to about 80*C. or higher and, thereafter, recovering an odor-improved and storage-stable olefinic derivative.

United States Patent [191 Takacs [451 Sept. 30, 1975 1 PROCESS FOR THEODOR REMOVAL OF MALODOROUS SULFUR CONTAINING OLEFINIC DERIVATIVES [75]Inventor: Edward Andrew Takacs. South Norwalk. Conn.

[73] Assignee: American Cyanamid Company.

Stamford, Conn.

22 Filed: Sept. 23. 1974 211 Appl. No.: 508.300

[51] Int. Cl. C09F 3/02; C10G 27/04; ClOG 29/22 [58] Field 01' Search260/675.5. 702. 669 A. 2 60/674 A. 677 A. 208/189. 196. 237. 282. 291

[56] References Cited UNITED STATES PATENTS 1.840.269 l/1932 Borgstrom208/196 2.395.055 2/1946 Lorand 260/675.5

2.593.761 4/1952 Johnston-1e t 208/191 2.670.319 2/1954 Ayers et a]208/196 2.744.054 1/1956 Pieters 208/196 2.779.807 1'/1957 Hinegardneret a1. 260/674 2.790.752 4/1957 Urban 208/196 2.945.068 7/1960 Booth260/586 3.278.562 10/1956 Thigpen 260/348 3.723.478 3/1973 Ohloff et a1260/675.5 X

Primary Examiner-Delbert E. Gantz Assistant Examiner-G. E. SchmitkonsAttorney. Agent. or Firm-Harry H. Kline [57] ABSTRACT There is provideda process for the upgrading of a malodorous. sulfur-contaminated.aliphatic. aromatic or cycloaliphatic olefinic derivative or mixturethereof which involves contacting said malodorous. sulfurcontaminatedderivative or mixture thereof with from 1 to 2 equivalents of aper(lower)alkanoic acid per mole of sulfur in said olefinic derivative.the amount of said acid being sufficient to oxidize the sulfur contenttherein. maintaining the treated solution at a temperature ranging fromabout l0C. to about 80C. or

higher and. thereafter, recovering an odor-improved and storage-stableolcfinic derivative.

11 Claims. No Drawings PROCESS FOR THE ODOR REMOVAL OF MALODOROUS SULFURCONTAINING OLEFINIC DERIVATIVES V I The present invention relates to anovel process for upgrading sulfur-contaminated olefinie derivatives.More particularly, it relates to a process for upgrading malodoroussulfur-contaminated aliphatic, aromatic or cycloaliphatic olefinicderivatives and mix t'ures'thereof by substantially removing theoffensive odor therefrom. Still more particularly,'the invention isconcerned with a method for treating said sulfur-contaminated olefinicderivatives or mixtures thereof with an organic peracid definedhereinbelow with particularity in anamount sufficient to obtainstorage-stable, odor improved olefinic derivatives.

In the past, attempts have been made to upgrade malodorous olefinicderivatives such as sulfate turpentine distilla'tes. Unfortunately, nonehas been wholly successful. One method, for instance, has been tosubject malodorous sulfate turpentine to steam distillation. Thisremoves low boiling sulfur contaminants. Since some of the sulfurimpurities which are naturally present have boiling points similar tothat of the terpene components, separation of these impurities presentsobvious difficulties. Another method has been to treat sulfateturpentine distillates'with an aqueous hypochlorite solution to sweetenits odor by oxidizing the sulfur compounds contained therein. Though theodor is logical side effects. Consequently, these method have not beenmet with universal acceptance; If a process could by developed whichobviates the difficulties of the prior practice, such would meet a needlong sought after in the art.

It is, therefore, a principal object of the invention to minimizeoffensive odors generally attributable to sul fur-contaminated olefin'icderivatives. It is a further object to'provide a relatively simple,economical and effective method for reducing offensive odors in olefinicderivatives 4 having" associated therewith sulfur.-. containingimpurities, such as mono and disulfides. Other objects and advantageswill becomeapparent to one skilled in the art from a reading of theensuing description. v

To this end, there is provided a relatively straightforward, simple andeffective method for attaining a marked improvement in malodorousaliphatic, aro matic or cycloaliphatic olefinic derivatives or mixturesthereof. Unexpectedly, the improvement is attained by admixing smallamounts of an organic peracid with the latter olefinic derivativeswithout adversely affecting said olefinic derivative by rearrangement,epoxidation and the like. Such admixture can take place over a widerange of temperature, usually from about minus C. to about 80C. orhigher. Surprisingly, the odor of the so-treated olefinic derivative ismarkedly improved and remains storage-stable with respect to odor over aprolonged period of time, whereas the olefinic derivative remainsunaffected notwithstanding the known conversion of olefms to epoxides inthe presence of peracids.

According to the process of the invention, any commercially availablesulfur-contaminated olefinic derivative or mixture thereof can besubjected to the action of an organic peracid over a temperature rangingfrom 10C. to 80C. or higher up" to the decomposition point of theperacid. In general, the addition of from about one equivalent to notmore than two equivalents of an organic peracid per mole of sulfur insaid olefinic derivative is sufficient to oxidize the sulfur contenttherein, thereby reducing any offensive odor therein to a highlycommercially acceptable level.

Any of a plurality of sulfur contaminated olefinic derivatives usuallycontaining more than 100 parts per million (ppm.) of sulfur present asan organic divalent sulfur species, can be treated in accordance withthe to be treated, are: performic acid, peracetic acid, perpropionicacid, p'erbutyric acid, perpentanoie acid and equivalents of the same,usually present from a 10 to 50 percent solution, by weight, in aqueousparent acid solution. Such per(lower)-alkanoic acids aswell as theirmethod for preparation are well known in the art. Generally, as abovestated, from one to two equivalents of said peracid per mole of sulfurin said olefinic derivative is sufficient to oxidize the sulfur content.A good operating amount of peracid based on200 to 5,000 ppm. sulfurusually ranges from about 0:1 to about 5.0 percent, and preferably from0.5 to 2 percent, all by weight of said organic peracid. Such amount ofperacid, when added to a sulfur contaminated olefinic derivative issufficient to reduce offensive odors therein to a highly commerciallyacceptable level. Of course, such amount is dependent upon the overallsulfur content. However, the utilization ofan amount in excess of 5percent of the peracid when not required to oxidize sulfur is notpreferred for the reason that the cost is increased and little, if any,additional advantage either by way of increasing the level or extendingthe period of odor control is attained. r v

It is an advantage of the process herein to effect the selectiveoxidation of sulfur impurities by converting the same to substantiallyless noxious impurities without affecting the unsaturated bonds of theolefinic derivative so-treated. Further, there is no need forspecialized equipment to carry out the process of the invention. Rather,the present process utilizes inexpensive equipment operable over a widerange of temperatures. Deodorization is attained upon the addition of,the peracid within a relatively short period of time, usually fromabout one second to 10 minutes after addition commences, although longerresidence time ranging from one to three hours can be used formanufacturing convenience without any deleterious effect.

In order to facilitate a further understanding of the invention, thefollowing examples are given primarily for purposes of illustratingcertain more specific details thereof. The scope of the invention is notto be deemed limited thereby except as defined by the instant claims.Unless, otherwise noted, the parts are by weight.

EXAMPLE 1 A suitable flask immersed in a water bath at 20C.

and equipped with stirrer and a thermometer is charged with 500 parts ofsulfate pine oil containing 5,200 ppm. of sulfur. Stirring is initiatedand 19.3 parts of 40% peracetic acid are slowly added at a rate so asnot to exceed a pot temperature of 30C. Temperature is controlled bymeans of the cooling bath. The total time of addition is minutes.

Resultant reaction mixture is stirred at ambient temperature for anadditional 45 minutes. It is then washed with water and then followed byan aqueous sodium carbonate solution wash to obtain an odor improvedproduct. Subsequent steam distillation affords 465 parts of a distillatewhose odor characteristics are markedly improved over those of thestarting-pine oil. On analysis, it is found that the sulfur content hadbeen reduced to 319 ppm.

Similar results are obtained when utilizing performic or perpropionicacid in lieu of peracetic acid in the above-stated procedure.

EXAMPLE 2 A suitable flask equipped with a magnetic stirring bar ischarged with (a) 100 parts of anethole containing 160 ppm. of sulfur and(b) 1.0 part of 40% aqueous peracetic acid. Resultant mixture is stirredfor one hour and then washed with water and subsequently steamdistilled, employing the procedure of Example l above, to yield 93 partsof organic distillate of significantly improved odor. On analysis, thedistillate exhibited a sulfur content of ppm.

Substituting perbutyric acid for the peracetic acid above and sulfurcontaminated B-pinene for anethole, similar results are obtained.

EXAMPLE 3 A suitable flask, immersed in a water bath and equipped with astirrer and a thermometer is charged with 100 parts of a particularlyfoul smelling crude sulfate turpentine containing 4,800 ppm. of sulfur.Stirring is initiated and 7.0 parts of 40% aqueous peracetic acid areslowly added at a rate so as not to exceed a pot temperature of C.

Subsequent to the addition of all the peracid, the resulting mixture isstirred at ambient temperature for one hour and is then washed withwater to obtain an odor improved product containing 200 ppm. sulfur. Itis next steam distilled as set forth in Example 1, to yield 93 parts ofa pleasant smelling distillate which is found to contain 95 ppm. ofsulfur.

EXAMPLE 4 Substituting a foul smelling, sulfur-contaminated gasoline forthe crude sulfate turpentine of Example 3 above, there is employed theprocedure of said Example 3 in every detail. A sweet smelling gasolineis obtained of substantially reduced sulfur content.

EXAMPLE 5 A 100 g. sample of malodorous cyclohexene, containing 5,000ppm. sulfur present as n-butyl ethyl sulfide, is cooled to 15C. and 4.0g. of 40% (by weight) peracetic acid is slowly added at a rate so as notto exceed a pot temperature of 25C.

After the peracid treatment is completed, the resulting mixture isstirred briefly at ambient temperature and is Washed successively with 2X 100 ml. portions of deionized H 0, 50 ml. of 5% Na CO and finally, anadditional 100 ml. of deionized H O.

The washed material is then steam distilled to yield 90 g. of a pleasantsmelling distillate which is found to contain 35 ppm. of sulfur.

I claim:

1..A method for the upgrading of a malodorous, sulfur-contaminatedaliphatic, aromatic, or cyclic olefinic derivative or mixture thereofwhich comprises the steps of: contacting said malodoroussulfur-contaminated olefinic derivative or mixture thereof with betweenabout 0.1 and about 5.0 percent, by weight, of a per(lower)alkanoicacid, at a temperature ranging from minus() 10C. to C., water washingthe so-treated olefinic derivative, and thereafter recovering anodorimproved, storage-stable, sulfur-reduced olefin.

2. The method according to claim 1 wherein there is employed from one totwo equivalents of the per(- lower) alkanoic acid per mole of sulfur insaid olefinic derivative.

3. The method according to claim 2 wherein the sowashed treated olefinicderivative is further subjected to distillation prior to recovering thesame.

4. The method according to claim 2 wherein the per(lower)alkanoic acidis selected from the group consisting of peracetic, perpropionic,perbutyric and perpentanoic acids.

5. The method according to claim 2 wherein the per(1ower)alkanoic acidis peracetic acid.

6. The process according to claim 2 wherein the per( lower)alkanoic acidis perpropionic acid.

7. The process according to claim 2 wherein the olefinic derivative tobe treated is crude sulfate turpentine.

8. The process according to claim 2 wherein the olefinic derivative tobe treated is crude sulfate pine oil.

9. The process according to claim 2 wherein the olefinic derivative tobe treated is sulfur-contaminated anethole.

10. The process according to claim 2 wherein the olefinic derivative tobe treated is sulfur-contaminated gasoline.

11. The process according to claim 1 wherein the per(lower)alkanoic acidis present in an amount ranging from 0.5 to 2.0 percent, by weight.

1. A METHOD FOR THE UPGRADING OF A MALLODOROUS, SULFUR-CONTAMINATEDALIPHATIC, AROMATIC, OR CYCLIC OLEFINIC DERIVATIVE OR MIXTURE THEREOFWHICH COMPRISES THE STEPS OF: CONTACTING SAID MALODOROUSSULFUR-CONTAMINATED OLEFINIC DERIVATED OR MIXTURE THEREOF WITH BETWEENABOUT 0.1 AND ABOUT 5.0 PERCENT, BY WEIGHT, OF A PER(LOWER)ALKANOICACID, AT A TEMPERATURE ANGING FROM MINUS(-) 10*C. TO 80*C., WATERWASHING THE SO-TREATED OLEFINIC DERIVATIVE, AND THEREAFTER RECOVERING ANODORIMPROVED, STORAGE-STABLE, SULFUR-REDUCED OLEFIN.
 2. The methodaccording to claim 1 wherein there is employed from one to twoequivalents of the per(lower) alkanoic acid per mole of sulfur in saidolefinic derivative.
 3. The method according to claim 2 wherein theso-washed treated olefinic derivative is further subjected todistillation prior to recovering the same.
 4. The method according toclaim 2 wherein the per(lower)alkanoic acid is selected from the groupconsisting of peracetic, perpropionic, perbutyric and perpentanoicacids.
 5. The method according to claim 2 wherein the per(lower)alkanoicacid is peracetic acid.
 6. The process according to claim 2 wherein theper(lower)alkanoic acid is perpropionic acid.
 7. The process accordingto claim 2 wherein the olefinic derivative to be treated is crudesulfate turpentine.
 8. The process according to claim 2 wherein theolefinic derivative to be treated is crude sulfate pine oil.
 9. Theprocess according to claim 2 wherein the olefinic derivative to betreated is sulfur-contaminated anethole.
 10. The process according toclaim 2 wherein the olefinic derivative to be treated issulfur-contaminated gasoline.
 11. The process according to claim 1wherein the per(lower)alkanoic acid is present in an amount ranging from0.5 to 2.0 percent, by weight.